Process of treating materials with cellulose derivatives



UNITED STATES PATENT OFFICE.

JOSEPH J. BYERS, OF EROOKLINE, MASSACHUSETTS, ASSIGNOR TO PRODUCTS SYNDI- CATE, INC., OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

PROCESS OF TREATING MATERIALS WITH CELLULOSE DERIVATIVES.

No Drawing.

To all whom it may concern:

Be it known that I, Josnrn J. BYERS, a citizen of the United States, and a resident of Brookl'ine, county of Norfolk, State of Massachusetts, (whose post-oflice address is 26 Broad street, Boston, Massachusetts,) have invented an Improvement in Processes of Treating Materials with Cellulose Derivatives, of which the following description is a specification.

This invention relates to methods of treating penetrable materials with a cellulose derivative, the object 'being to improve such materials with respect to certain desirable qualities.

The invention will be best understood by reference to the following description which illustrates by way of example the application of one form of the process to a specific case, while its scope will be more particularly pointed out in the appended claims.

The preferred manner of carrying out the method is to treat the material with a cement-like substance consisting of or including a cellulose derivative in solution and containing a quantity of non-oxidizing oil, and the best results are apparently obtained by thoroughly impregnatmg the material with the cement and oil. a

The materials comprising the cement and the/proportions in which they are mixed may be varied within wide limits. A suitable cement, for example, may be prepared by dissolving some cellulose derivative, such as a soluble nitro-oellulose, for example, celluloid, in a suitable solvent, which may be, for exam le, acetone and alcohol in equal parts; if, or illustration, celluloid and acetone and alcohol are used, one pound of celluloid to one gallon of solvent may be em loyed with good results. To this is prefera' ly added a substantial amount of some non-oxidizing or non-drying oil, preferably a vegetable oil. This, for example, may be castor oil in the proportion of eight ounces to one gallon of solvent.

The preferred method of treatment is to immerse the material in a bath composed of the cement. For illustration, a bath may be prepared of suflicient volume in proportion to the mass of the material to be treated to maintain the material immersed for the required time thoroughly to impregnate it o p Q moisture in the leather or other material and without impairing the fluidity or effectiveness of the cement. The tank or other r8- Speciflcation of Letters Patent.

Application filed April 19,

Patented Aug. 23, 1921.

1916. Serial No. 92,320.

ceptacle employed for the bath is preferably closed to prevent any substantial evapora-- tion of the solvent during the treatment of the material, and is also preferably provided with suitably controlled heating means so as to maintain the bath at a suitable temperature. The temperature of the bath is preferably maintained at a point above the normal temperature of the air, but below that which would rapidly evaporate the solvent or impair the qualities of the oil or the material to be treated. In the treatment of leather with a cement constituted as described and containing the stated amount of castor oil, the temperature should be preferably less than 160 F. Good results are had from temperatures'varying from 125 to 130F. Porous materials such as leather usually hold absorbed more or less hygroscopic moisture. To facilitate the impregnation of the material with the cement, it is preferable to remove substantially all water and hygroscopic moisture from the material before its treatment. This may be accom plished in any desired manner, but, in the case of leather, a simple method is to expose the material to a suitable dryingtemperature for a period long enough to drive out the moisture. The time and temperature required will differ for different mater als and different masses of the same material. In the ,case of sole leather, for example, the leather may be hung or spread over night in a drying room or drying oven at a temperature of from 120 to 150 F. In the case of some textile fabrics or thin sheet materlals, the material may be prepared for immersion by passing the same slowly through a dryin room or drying apparatus. I

Irefera'bly also the materlal should be handled and the treatment carried outina room where the air has a low humidity so that in passing from the drying operation to the immersion, the material may have no opportunity to absorb or collect any substantial or detrimental amount of moisture.

While no particular temperature in the room where the operation is carried out is essential to the lnvention, good results arosecured. where it is maintained between 70 and 80 F.

By expelling substantially all of the immersing it while a dry state, the peri or particles of the mass.

meation or impregnation of the material is facilitated and it is possible to impregnate the entire mass with the cement, the nonoxidizing oil in the latter apparently replacing the moisture in the individual fibers With'the material dried as described, it may be immediately plunged into the bath and there maintained immersed in the presence of heat and the oil for a long enough period thoroughly to impregnate it with the oil and cement.

The period during which the immersion may be profitably-continued will vary with the material and its thickness. For sole leather, for example, it may require from two to six hours, according to the thickness. In the case of some thin, permeable, sheet material, a few minutes or less will sometimes suffice. Preferably the immersion is continued for an appreciable. period sufficiently prolonged to impregnate the mate rial throughout. In the presence of heat and immersed in the solution, the material soon becomes impregnated with the cement. In the case of fibrous material such as leather, the fibers, I believe, become charged with the oil with perhaps more or less cement, while at the same time they become coated over by and incased in the cement which permeates the entire mass.

After removin the material from the bath, it may then be dried. The effect of this is apparently to unite the fibers or particles into a homogeneous mass, leaving the oil sealed in the .particles or fibers and pro,- tected by the cement which, as I believe, incases them and binds them together throughout. The material treated by this method may be thoroughly impregnated throughout as distinct from a mere surface coating or a coating which has an anchorage or impregnation of limited depth. Leather treated by this method acquires the property of repelling water, has great durability and density and a high degree of flexibility. Its water repellent properties, moreover, are long continuing, which I attribute to the .fact that the oil which is sealed into the induced by subjecting it to pressure before Y completely drying. If it is desired to compact the cement-impregnated material, the latter, after being removed from the bath,

maybe subjected to one or more pressin operations tending to press and bind the bers more closely together. This pressing operation may be carried out in any desired manner, as, for example, in a press or by passing the material progressively between preferably heated rolls. In the case of leather, for example, it may be run between successive pairs of'heated rolls, the members of successive pairs being separated by graduated distances so that the material is gradually compacted and rendered more dense, preventing its expansion when subjected to moisture.

- In the case of some materials, as, for example, in the case of sole leather, a greater compactness may be secured byallowing the The cement-impregnated material may, if.

desired, be coated with one or more coatings of the cement solution or with'any other suitable solution of a cellulose derivative either for the purpose of finishing the surface, or for any other purpose. For example, to surface-coat cement-impregnated leather, the latter after having been impregnated, compressed and dried, may then be surfacecoated with a cement solution. This solution by way of illustration may be similar to that composing the bath. With the coating partly dried, it may then be run between hot compression rolls, and this operation may be repeated as many times as is desired.

In the case of leather, the product of this process is characterized by greater toughness, compactness and durability than the original leather before "treatment and) is substantially and permanently water-repellent. While tougher and more durable, it is highly. flexible because of the oil-filled, cement-coated fibers. rability, toughness, compactness and waterrepellent qualities may be so imparted to cheap or. inferior grades of leather as to make them available for uses and purposes not heretofore possible, and as equal or better substitutes for leather of more expensive grades. a

In the case of leather, a product may be produced which while water-repellent is n t By this process duable wholl impervious to air, rendering it availfbr certain uses where some degree of porosity is desired and where such a material as rubber, for example, is undesirable. Apparently the fibers become incased with the cement after the leather has been immersed without necessaril wholly filling the interstices between the fi rs or wholly expelling the air from within the same. This fibrocellular structure of the leather may be preserved to a greater or less extent according to the degree to which the compacting operation is carried. g The treatment of leather or textile materials by my process assists in preserving the same. When employed for footwear, for example, it resists the rotting action which, in the case of ordinary leather, is due in part a to the presence of ammonia. in the perspiration from the foot.

' I donot herein claim the product which is herein described as produced by the disclosed method, -.the roduct being claimed in my co-pending app ication Ser. No. 141,664, now Patent No. 1,327,197.

While I have herein described for purposes of illustration the steps in detail by which one form of my process may be carried out, it is to be understood that the invention is not limited to the exact details specified, but may be varied within suitable limits without departing ,from the spirit thereof, and furthermore, that while I have illustrated the same with reference to the treatment of leather, other fibrous materials and penetrable materials other than fibrous materials may be treated by my process with beneficial results.

Claims: I

1. The method of improving .penetrable material which consists in immersing the material in a cement bath consisting of a cellulose derivative in a suitable solvent and a non-oxidizing oil, maintaining the material in said bath in the presence of heat until impregnated throughout with the oil and cement, removing the same from the bath, and drying the same. 1

2. he method of improving penetrable material which consists in immersing the material while substantially free from moisture in a cement bath consisting of nitrocellulose in a suitable solvent and a nonoxidizing oil, said solvent being in suflicient proportions and said bath being of sufiicient volume in pro ortion to the mass of material to maintain the fluidity of the cement during the immersion of the material, maintaining the material in said bath in the presence of heat for a sufiicient time to cause the oil and cement to penetrate throughout the mass of material, removing the material from the bath and drying the same.

3. The method of improving penetrable material which consists in removing substantially all moisture therefrom, immersing it.while still free from moisture in a cement bath consisting of a cellulose derivative in a suitable solvent and a non-oxidizing oil, maintaining the material in the presence of heat for a sufiicient time to cause the oil and cement to penetrate throughout the mass of the material, withdrawing it from the bath, and drying the same to set the cement.

4. The method of improving penetrable material which consists in removing substantially all moisture therefrom, immersing it while still free therefrom in a cement bath consisting of a cellulose derivative in a suitable solvent and a non-oxidizing oil, maintaining the material in said bath in the presence of heat for a suflicient time to cause the oil and cement to penetrate through the mass of nmterial, compacting the mass further to unite the cemented particles, and dryin the compacted mass.

5. The meth of improving penetrable material which consists in withdrawing hygroscopic moisture from the material, immersing it while free therefrom in a cement bath consisting of a cellulose derivative in a suitable solvent and a non-oxidizing oil, maintaining the temperature of said bath at from 120 to 170 F., main thematerial in said bath until thorough y impregnated with said oil and cement, removing it from the bath, and drying the same.

6. The method of improving penetrable sheet material which consists in dr the material to remove substantially all moisture therefrom, immersing it while still dry and in a dry atmosphere in a cement bath consisting of nitrocellulose in a suitable solvent together with a non-oxidizing oil, maintaining the material in said bath for a suflicient time to cause the oil and cement to penetrate throughout themes: of the *material, maintaining the temperature of the bath during immersion at a point less than the boiling temperature of the solventiand above the temperature of the surrounding atmosphere, said bath being of sufiicient volume to maintain the immersion of the material during the period of treatment, compacting the mass by heat and presure, and drying the compacted mass to set'the cement.

7. The method of improving penetrable material which consists in immersi the material while substantially free from m'oidzure in a cement bath consisting of nitrocellulose in a suitable solvent and in the proportions of one gallon of solvent to one pound of nitrocellulose and containing a non-oxidizing oil, mainta' the bath at a temperature of from 120 to 160 F., keeping the material in said bath until the oil and cement have penetrated throughout the mas of material, expelling the excess of cement, compacting the mass by heat and pressure, and drying the compacted mass.

8. The method of improving penetrable material which consists in immersing the material in a'bath containing a solution of ahcellulose derivative, maintaining the material in said bath in the presence of heat and a non-oxidizing oil until impregnated, withdrawing the same from the bath and partly drying to set the cement near the surface, compacting the partly dried material further to unlte the particles thereof, and completely drying the same.

9. The method of improving sheet material which consists in impregnating the same throughout in the presence of heat with a cement having a cellulose derivative in solution and a non-oxidizing oil, and thereafter pressing the cement-impregnated sheet.

' 10. The method of improving .material which consists in impregnatin it in the presence of heat with a solution of a cellulose derivative and a non-oxidizing oil.

11. The method of improving material which consists in immersing it in the presence of heat in a bath having a cellulose oxidizing oil, heating said bath, maintaining the material in said heated bath until the same is thoroughly impregnated, and compacting themateria-l when removed from the bath to compress and condense the impregnated body thereof before drying.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

- JOSEPH J. BYERSU Witnesses:

ROBERT H. KAMMLER, -THOMAS B. Boo'rn. 

